"Unlike static tests, where loads are applied to the airplane structure to simulate both normal operation and extreme flight conditions, fatigue testing is a much longer process that simulates up to three times the number of flight cycles an airplane is likely to experience during a lifetime of service," said Jim Ogonowski, structures vice president, Boeing Commercial Airplanes.

While the structural test program already has validated the strength of the airframe, fatigue testing looks at long-term, continued use. This is the natural progression of testing on a new airplane and part of the process to achieve U.S. Federal Aviation Administration certification.